This invention relates to improvements in pyroelectric power conversion and more particularly to the conversion of heat to electrical energy by the use of one or more capacitors having temperature dependent capacitance and novel regenerative means for thermally cycling such capacitors, there being means for charging the capacitor during the cool portion of its thermal cycle so that upon subsequent heating and concomitant decrease in the dielectric constant of the capacitor, the charge therein is caused to expand into associated circuitry in which it is available to do electrical work.